Street curbings made of synthetic resins

ABSTRACT

A street curbing comprising an outer polyethylene shell reinforced with fiberglass. The shell is filled with high density polyethylene foam.

United States Patent Wallace [4 1 Oct. 17, 1972 [54] STREET CURBINGS MADE OF 802,772 10/1905 McCoy ..94/32 SYNTHETIC RESINS 3,179,397 4/1965 Cleereman ..114/219 X [72] Inventor: Robert L Wallace 6502 westland 329,342 10/1885 Sutton ..94/31 Road Bethesda Md 20034 3,491,660 l/1970 Kwasney ..94/31 3,520,082 7/1970 Smith ..94/31 X [22] Filed: Jan. 21, 1971 1,471,074 10/1923 Trester ..94/31 Appl' 108578 Primary Examiner-Jacob L. Nackenoff R l s. Application Data Attorney-Lane, Aitken, Dunner & Ziems [63] C0ntinuationin-part of Ser. No. 830,700, June 5, 1969, abandoned. [57] ABSTRAC A street curbing comprising an outer polyethylene [52] US. Cl ..94/31 Shell reinforced with fibergiass- The Shell is filled with 511 Int. Cl .E01c mm high density P y y e fem [58] Field of Search ...52/169, 300; 94/31, 32; 4/172,

[56] References Cited 6 Claims, 4 Drawing Figures UNITED STATES PATENTS 3,411,304 11/1968 Miller ..61/48 l3 ll '9 23 v r. :3. 2;; 3.. o h l7 f 4 1' z, I2

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STREET CURBINGS MADE OF SYNTHETIC RESINS REFERENCE TO RELATED APPLICATION This application is a continuation-in-part of applica- 7 tion Ser. No. 830,700, filed-June 5, 1969, entitled Steet Curbing Made of Synthetic Resins, now abandoned.

BACKGROUND OF THE INVENTION This invention relates to street curbing and, more particularly to curbing with an improved construction.

Because concrete curbing deteriorates and has to be replaced after only a few years on downtown city streets, many municipalities are now using granite curbing. Granite curbing is very durable but its cost is about twice that of concrete because of the equipment and skilled labor required to install the granite.

SUMMARY OF THE INVENTION The present invention provides a curbing which is equally as durable as granite but which is much lighter in weight and therefore can be shipped and installed at a much lower cost than the granite curbing. Moreover,

the curbing of the present invention is much more easily replaced than the granite.

In accordance with the present invention, the curbing comprises an outer shell of a strong synthetic resin reinforced with fiberglass and filled with a high density synthetic resin foam. The curbing is provided with means to hold it in place in concrete backing, which is also used with the granite curbing of the prior art. The resulting curbing is strong and durable, is not attacked by salt, and yet is much lighter in weight than the granite curbing used in the prior art. Moreover, when a section of the curbing becomes damaged it can be easily replaced simply by cutting out the damaged section and putting in a new section which is easily cut to fit to replace the damaged section.

Accordingly, an object of the present invention is to provide an improved street curbing.

Another object of the present invention is to provide a durable street curbing which is much lighter in weight than the curbing of the prior art.

A further object of the present invention is to pro vide a curbing which can be easily replaced when a section of the curbing becomes damaged.

Further objects and advantages of the present invention will become readily apparent as the following detailed description of the invention unfolds and when taken in conjunction with the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 illustrates a plan view of a street with the curbing of the present invention in place;

FIG. 2 is a sectional view taken along the lines 2--2 in FIG. 1;

FIG. 3 is a perspective view partially broken away illustrating an outer shell of curbing of the present invention; and,

FIG. 4 is a sectional view similar to that shown in FIG. 2 and illustrates another embodiment of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS In FIGS..1 and 2, reference number 11 generally designates the curbing of the present invention and the reference number 12 designatesthe pavement of the street, beside which the curbing is located. The curbing 11 comprises an outer shell 13, which is made of a strong durable synthetic resin, preferably polyethylene, reinforced with fiberglass. The polyethylene should have a molecular weight of greater than 6,000 and preferably of about 25,000. The tensile strength of such polyethylene is in the range of 3,100 to 5,000 psi and the compressive strength is 2,400 psi. The polyethylene will resist continuous heat up to 250 F.

The outer shell 13 is open at both ends and is filled with a high density rigid synthetic resin foam 17, which preferably is polyurethane foam. The density of the foam is such to have a weight in'the range of IO to 30 pounds per cubic foot. The use of a foam filler prevents water from getting inside of the shell and the use of such high density rigid foam improves the strength of a the curb against crushing. The foam, however, may be left out leaving the outer shell hollow and the structure will still be sufficiently strong to withstand the crushing forces to which it will be subjected in use as a curb.

The shell 13 consists of four wall sections, a bottom wall 18, a back wall 19, a front wall 21 adjacent to the street paving 12, and a top wall 23. The shell is approximately rectangular in section with the top wall 23 and the bottom wall 18 being parallel and the back wall 19 being perpendicular to the top and bottom walls. The front wall 21 angles slightly outward to provide a slope to the outside surface of the front wall.

As best illustrated in FIGS. 2 and 3, the curbing shell is also open at the corner between the back wall 19 and the bottom wall 18. This opening, which extends throughout the length of the shell, facilitates the filling of the shell with the foam. Spaced along the length of the bottom wall 18 of the shell and the back wall 19 are anchor bolts fixed to the shell and having L-shaped foot portions which extend out from the shell walls. The curbing 11 is held in place adjacent to the street pavement by concrete backing 27 which extends along the bottom wall 25 and up over a portion of the back wall 19 throughout the length of the curbing. The anchor bolts 25 are embedded in the concrete backing so that the L-shaped foot portions lock to anchor bolts in the concrete to hold the curbing firmly in place. As in the granite curbing of the prior art, the concrete backing 27 is covered up to the top of the curbing with dirt or sidewalk paving. The curbing is 12 inches high measuring between the outer surfaces of the bottom wall 18 and the top wall 23. The backing 27 covers all but the top 4 inches of the back wall 19. The street pavement 12 leaves 6 inches measured vertically of the front wall 21 exposed. The slope of the front wall 21 is such that the horizontal distance from the corner at which the planes of the outer surfaces of the top wall 23 and front wall 21 intersect to the street paving 12 is one-half inch. The actual corner between the top wall 23 and front wall 21 is rounded with a one-half inch curvature. The above described dimensions conform with those required in conventional street curbing. The length of the curbing sections will normally range from 4 to 12 feet.

To install the curbing, the concrete backing is formed in place generally in a shape to receive the curbing. While the concrete backing is still wet the curbing is situated in place on the backing so that the anchor bolts embed into the concrete backing.

Because of the materials of which the curbing of the present invention is made, it is much lighter in weight than the granite curbing of the prior art and therefore can be installed much more easily and requires much less skill in installing than the granite curbing of the prior art. Should a portion of the curbing become damaged, it can. be replaced very easily simply by cutting out the damaged section, knocking out the anchor bolts and then replacing the damaged section with a new curbing section. The holes in the concrete backing from which the anchor bolts 25 are pulled, will be refilled with concrete to grip the anchor bolts of the new curbing section and hold it in place.

In the embodiment shown in FIG. 4, instead of using anchor bolts to hold the curbing section in place, the curbing shell is formed with curved outwardly extending walls 29 and 31, which extend from the corner where the shell is open to receive the polyurethane foam. The wall extensions 29 and 31 extend throughout the length of the curbing section and are embedded in the concrete backing 27 to hold the curbing in place. The remainder of the curbing of the embodiment as shown in FIG. 4 is the same as that in FIG. 2.

The embodiment of FIG. 4 is to be used in environments which are subject to severe temperature extremes causing extensive expansion and contraction in the length of the shell 13 relative to the concrete backing. A lubricant, such as form oil, is placed on the embedded wall extensions 29 and 31 and between concrete backing 27 and the front and bottom walls 18 and 19 to permit the shell 13 to slide in the concrete backing and thus permit the thermal expansion and contraction of the shell relative to the concrete backing.

The above description is of preferred embodiments of the invention and many modifications can be made thereto without departing from the spirit and scope of the invention, which is defined in the appended claims.

I claim:

1. In combination with a paved street, a curbing at the edge of said street comprising an outer shell, approximately rectangular in section made of a relatively rigid fiber-reinforced synthetic resin and having a vertically extending front wall facing said street and extending above the top surface of said street, the paving of said street covering a portion of the vertically extending front wall of said curbing, and means anchoring said shell in place at the edge of said street, said anchoring means comprising a concrete mass for said curbing and anchoring elements extending from the back and bottom of said shell embedded in said concrete mass and locking said curbing to said mass.

2. In a combination as recited in claim 1 wherein said anchor elements are constructed so that said shell is free to expand and contract relative to said concrete mass.

3. In a combination as recited in claim 1 wherein said anchoring means includes means fixed to said shell and embedded in said concrete backing and a lubricant between said embedded means and said concrete backing, said embedded means being shaped to permit said shell to expand and contract relative to said backing aided by said lubricant.

4. In a combination as recited in claim 1 wherein said shell is filled with a synthetic resin foam.

5. In a combination as recited in claim 1 wherein at least one of said anchoring elements comprises an extension of the wall of said shell embedded in said concrete mass, extending parallel to the horizontal axis of said shell throughout the horizontal length of said shell, and shaped to be in more than plane.

6. In a combination as recited in claim 1 wherein at least one of said anchoring elements embedded in said concrete mass includes a shank portion and a foot portion, said foot portion projecting angularly from said shank portion to lock such anchoring element in said concrete mass. 

2. In a combination as recited in claim 1 wherein said anchor elements are constructed so that said shell is free to expand and contract relative to said concrete mass.
 3. In a combination as recited in claim 1 wherein said anchoring means includes means fixed to said shell and embedded in said concrete backing and a lubricant between said embedded means and said concrete backing, said embedded means being shaped to permit said shell to expand and contract relative to said backing aided by said lubricant.
 4. In a combination as recited in claim 1 wherein said shell is filled with a synthetic resin foam.
 5. In a combination as recited in claim 1 wherein at least one of said anchoring elements comprises an extension of the wall of said shell embedded in said concrete mass, extending parallel to the horizontal axis of said shell throughout the horizontal length of said shell, and shaped to be in more than plane.
 6. In a combination as recited in claim 1 wherein at least one of said anchoring elements embedded in said concrete mass includes a shank portion and a foot portion, said foot portion projecting angularly from said shank portion to lock such anchoring element in said concrete mass. 